I second that. It may still heal since he is very small. Gill curl from the research I have done is really just any abnormal shape of the membrane that covers the gills. Could be stress or bad water params. I added lots of aeriation and extra filtration and my little guy seems to be getting rid of it. He came to me with all sorts of problems. Gill curl and fin and tail rot. Makes me mad, but I think he will do fine as all his tank params are perfect and I am fattening him up on blood worms. The fin and tail rot are under controll so I am sure he'll do great. Good luck with yours.
